(a) Field of the Invention
The present invention relates to clips holding a cable, and more particularly to clips holding a cable, which is built into a security fence in a pattern, for raising an alarm against intrusion or tampering by cutting off or damaging the cable in emergencies.
(b) Description of the Related Art
A security fence is a structure built to protect facilities (or areas). A conventional way of guarding facilities or areas has been to build a security fence around them and patrol this fence.
Another way was to equip the security fence with an optic cable and monitor the distortion of light, which flows through the optic cable to detect intrusion or tampering. This is well-known in a plurality of previous disclosures such as U.S. Pat. Nos. 4,275,294; 4,371,869; 4,399,430; 4,450,434; 4,558,308; 4,676,485; 4,680,573; 5,134,386; 5,416,467; 5,592,149; and Korean Patent Nos. 20-0205489, 20-0205490.
According to the conventional arts, an optic cable is built into a security fence in a zigzag pattern. The optic cable has a pattern smaller than the size of a man such that an intruder cannot get though the pattern without breaking it. In other words, an intruder cannot make a hole in the fence large enough to pass through without cutting off or damaging the optic cable. Any transformation or damage to the optic cable would distort the flow of light therein, raising an alarm.
FIG. 1 illustrates a security fence 10 installed with an optic cable 12 according to a conventional art.
As shown in FIG. 1, the optic cable 12 is installed on the security fence 10 in a zigzag pattern. Here, clips 14 are holding the optic cable in the zigzag pattern.
FIG. 2 is an enlarged view of the zigzag pattern of the optic cable 12, and FIG. 3 is an enlarged view of the clips 14 according to the conventional art. Henceforth, the clips 14 are illustrated in detail with reference to the accompanying drawings, FIGS. 4 to 6.
According to the conventional art, the clip 14 is basically composed of a first part 16 and a second part 17. The first part 16 comprises a disc-shaped portion 18 and a stem portion 20 (refer to FIG. 4). The first part 16 would substantially have a T-shaped cross section taken along its mid-line, as can be envisioned in FIG. 4.
On the other hand, the second part 17 is generally disc-shaped and connected with the first part 16 (refer to FIG. 5). A hole 22 centrally located in the second part 17 is for accepting the stem portion 20 of the first part 16 and being connected therewith. The second part 17 also has a protrusion 24 over the external circumferential surface. The protrusion 24 has first, second, third, and fourth channels 25, 26, 27, and 28 passing therethrough.
In order to form a zigzag pattern, the first and second channels 25, 26 should be artificially installed with an optic cable 12 therethrough. The third and forth channels 27, 28 should be installed with another optic cable 12 therethrough.
Next, as illustrated in FIG. 6, the stem portion 20 of the first part 16 is manually interposed through a hole 22 centrally located in the second part 17. Then, an end 23 of the stem portion 20 of the first part 16 is flattened or deformed by riveting, or the like, to be connected with the second part 17.
However, this conventional clip has a drawback of hardly holding an optic cable in a pattern.
For example, the clip can be cumbersome to manually install, since the optic cable 12 must be fixed relatively shallow into the first through forth channels 25, 26, 27, and 28 of the second part 17, while riveting the first part 16 on the second part 17. In addition, the exposed open edges between the first and second parts 16, 17 can be exploited by a would-be intruder in an attempt to pry the first part 16 off from the second part 17, while gripping the second part 17 with a tool (e.g. locking pliers).
Another potential drawback is the exposure of the flattened end 23 of the stem portion 20. A would-be intruder could attempt to cut off the flattened end 23 of the stem portion 20, and if successful, the first part 16 could be disassembled from the second part 17.
If the would-be intruder could gently remove at least one clip 14 and separate the weave pattern of the optic cable 12, the would-be intruder might gain undetected access to secure facilities.